Self-aligning hammer



' y J. BURNETT 2,282,932

- SELF-ALIGNING HAMMER Filed May 6, 1959 Patented May 12, l 1942 UNITED STATES PATENT OFFICE 2,282,932 7 SELF-ALIGNING HAMMER Robert J. Burnett, Woodstock, Ill. Application May 6, 1939, Serial No. 272,106 3 Claims. (01. 145-29) This invention relates to improvements in hand hammers, and more particularly concerns a new and improved hammer having a selfaligning striking face.

Unless skill and care are exercised in the use of drive the nail-head into position flush with the surface of the part being nailed, any angularity of the striking face of the hammer relative to the plane of the surface may leave a disfiguring impression of the edge of the hammer head. The surface marring effects of an unaligned hammer face may also be seen where an object is pounded with a hammer for other reasons than to drive a nail, as, for example, where a mechanic has been required to pound a machine part or tool.

An object of the present invention is to provide an improved hammer which will overcome the foregoing problems, and which more particularly will assure level engagement between the striking face of the hammer and the surface of the driven or pounded part even though the angle of approach is not perpendicular.

Another object is to provide simple and inexpensive means for rendering the striking face of a hammer head self-aligning upon impact with the surface against which the hammer blow is directed.

Other objects and advantages will become apparent in the following description and from the accompanying drawing in which:

Figure 1 is a perspective view of a hammer embodying the invention and showing the hammer at the moment of impact with a nail.

Fig. 2 is a longitudinal sectional view through the hammer head.

Fig. 3 is an exploded assembly view of the self-leveling nose portion of the hammer head.

Fig. 4 is a perspective view of a slightly modified form of striker block.

While the invention is susceptible of various modifications and alternative constructions, I have shown in the drawing and will herein describein detail, the preferred embodiment, but

it is to be understood that I do not thereby intend to limit the invention to the specific form disclosed, but intend to cover all modifications and alternative constructions falling within the spirit and scope of the invention as expressed in the appended claims.

' the hammer. The

' The invention may, for example, be embodied in a hammer III of any preferred type including a handle ll supporting a transverse hammer head 12. In the present instance, a claw head having a striking nose or tip I3 is 'shown.

According to the present invention, the hammer tip l3, instead of being formed with an integral end striking face, is provided with an adjustable striker block l4 having a striking face I 5 which will normally erably universal adjustment about an axis perpendicular to the handle H, so as to compensate for angular misalignment of the striking face l5 relative to the impacted surface not only longitudinally but also laterally of the hammer.

In the preferred form, the striker block [4 ball, the substantially flat dithereof being approximately coextensive in area with the end of the hammer tip l3 and constituting the striking face l5 .of semi-spherical surface of the striker block defines a bearing face I 6 adapted to rest for universal rocking adjustment in a complemental partial spherical socket I1 formed coaxially in the end of the hammer tip l3.

While the socket l7 permits self-adjustment of v the block ing so as 7 force of the hammer blow.

A suitable yieldable connection tain the striker block l4 adjustably in bearing engagement in the socket H. Such connection may be provided by an appropriately tensioned coil spring l8 conveniently disposed or housed in an axial recess or bore I9 opening inwardly from the socket IT. The inner end of the I4, it also affords a solid impact backserves to mainremovably hooked through an eye 2| in a central lug 22 projecting inwardly from the spherical surface- I 6 of the striker block I 4. in Fig. 2, the lug 22 may be formed on the end 23 which is threaded into the striker block I4. In the modified form of Fig. 4, the spring-receiving lug is formed as a boss 24 integral with the block I 4. As best seen in Fig. 3

tend to assume a centered 7 not to impair appreciably the driving 2 the anchor pin may have a central annular groove 20 which will receive and maintain the inner end of the spring l8 in centered position.

In one suitable method of assembling the striker block M with the hammer head [2, the spring l8 may be connected to the anchor pin 20, and then stretched out of the well l9 and hooked onto the striker block. Then, upon releasing the striker block [4, contraction of the connecting spring l8 will pull the semi-spherical rear face thereof snugly into the complementary bearing socket ll of the hammer tip.

As a result of the axial interconnection of the striker block I4, the connecting spring 18 and hammer tip l3, the tension of the spring will act to hold the striker block l4 centered-whereby the striking face 15 will normally lie in a plane perfectly perpendicular mer tip Yet, due to the the connecting spring capable of substantially universal movement to assume the level of a surface impacted in the use of the hammer. Thus, if in striking an object, such as a nail-head (Fig, 1), with the hammer, the axis of the hammer-tip I3 is not perpendicular to the plane of the top of the nailhead at the moment of impact, the striking face 15 will nevertheless seek full contact with and assume the level of such plane automatically by rocking of the striker block l4, thereby compensating for the inaccuracy of approach. Due to the large area of direct semi-sphericalbearing contact of the striker block within the socket II in the hammer tip, little, if any, driving force is lost in the hammer blow. Moreover, even though the striking face l5 may tilt in any direction relative to the axis of the impact tip I3, the axial center of the striking face will not shift relative to the impact-tip axis, thus assuring maximum impact force from a blow struck with the hammer. Immediately after the force of the hammer blow is released, the connecting spring l8 will pull the striker block back to its normal centered position.

From the foregoing it will be apparent that the present invention provides a, novel self-leveling hammer construction which is adapted for use like any ordinary hammer of the same type but which avoids the damaging effects of unevenly directed hammer blows upon the surface of the object being struck. Moreover, the. novel hammer construction is simple, strong, easily assembled and may be manufactured at low cost.

I claim as my invention:. 7 r

1. A self-aligning hammer comprising, in combination, a handle, a hammer head at one end of the handle having a hollow' tip portion projecting laterally relative to the handle, said tip portion having a partially spherical socket opening from the striking end thereof, a semi-spherend of said tip portion ical striker block bearing slidably in said socket and having a generally plane striking face of a diameter substantially corresponding to the end of said tip portion, and means within said tip portion for yieldably connecting said striker block in centered relation within said socket but permitting universal rocking movement of said striker so that said striking face may squarely engage a surface being hammered although the angle of approach is not perpendicular to said surface, the depth of said socket being such that said striker block projects sufiiciently beyond the to avoid direct contact between the tip portion and said surface during to the axis of the ham yieldable character of IS the striker block I4 is' a hammer blow even though of the character described, a

head, said tip portion being .tive to the axis of the tip the striker block may be caused to rock substantially.

2. In combination in a self-aligning hammer hammer head including a tip portion, a handle carrying said formed with a centered. partially spherical socket at its forward end and an axial recess opening-inwardly from said socket, a striker block in the form of a halfball seated in slidable bearing engagement in said socket and being adapted for universal adjustment movement therein, the diameterical face of said striker block being substantially coextensive in area with the end of the hammer tip and forming the striking face of the hammer, and resilient means within said recess arranged to be effective at the center of the semi-spherical face of said striker block for holding the striker block seated in said socket and centered so that said striking face will normally lie in a plane perpendicular to. the axis of the tip portion but may adapt itself by movement of the striker block in the socket to abut a surface struck thereby squarely during a hammer blow despite inaccurate approach in the swing of the hammer.

3. A self-aligning hammer of the character described comprising, in combination, a head including a tip portion, a handle at right angles to said tip portion for swinging said head, a halfball striker block, said tip portion having a centered partially spherical socket in its outer end complementary to and having the semi-spherical face of saidstriker block seated in uniformly slidable bearing relation therein, said socket being of suchldepth that saidsemi-spherical face is onlypartially received therein and the diametrical face of. the striker block thus projects beyond the end of said-tip portion to form the striking surface of the hammer, and resilient means holding said striker block yieldably seated in said socket in such manner that the axial center of said diametrical face will not shift relaportionirrespective of the tilted angle assumed by saidface upon impact with a surface being hammered a ROBERT J. BURNETT. 

